(a) Field of the Invention
The present invention relates to a hollow driving module.
(b) Description of the Related Art
In general, an industrial robot configures a joint with a solid decelerator, a servo motor, and a brake, and controls a position or a speed by receiving feedback of the position and the speed by using a solid rotation angle sensor 30 of a shaft 20 of the servo motor 10 as illustrated in FIG. 1. However, in this case, a power line 40 and a sensor line of the servo motor 10 are exposed outside of a robot main body 50.
In a manufacturing business field using a robot, lightness and simplification of a robot have been recently demanded for densifying an operation process and space.
In order to achieve a light and simplified industrial robot, it is necessary to commonly use components and the components should be densely disposed in order to decrease weight and volume by integrally forming the decelerator (not illustrated) and the servo motor 10 configuring the joint of the robot, and the components need to be formed in a hollow type so that a power supply line, the sensor line, and various utility lines 70 pass through central axes of the components thereof.
Accordingly, a robot manufacturing company shows an action to respond to the demands of the lightness and simplification of the robot by making an actuator 80 become light and slim by commonly using the components and a high-density arrangement design of the components by integrating the servo motor 10, the decelerator (not illustrated), and the brake (not illustrated) as illustrated in FIGS. 1 and 2. Further, the simplification of the robot is attempted by designing so that a hole is formed at a center of the integrated actuator 80 and the power line 40 and the utility line 70 pass through the actuator 80.
Korean Patent Registration No. 0642307 entitled “Hollow Motor Decelerator” discloses the invention related to a hollow motor decelerator in which each of a main body of a hollow decelerator and an entirety of a hollow motor is assembled through separate processes.
In the meantime, the aforementioned hollow driving module for driving the link by using the hollow motor transmits torque to the output side (link) by reducing a rotation speed of the motor through the decelerator and amplifying the torque.
However, torque loss is essentially generated in the hollow driving module during the process, so that it is difficult to measure an accurate torque and an accurate rotation angle of the output side.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.